At a previous company, I joined a team that had to deliver something a year before I joined. All previous teams assembled to deliver that had failed and had been fired. That the company didn't have that feature was deeply embarrassing, the competition mentioned having it in the first line of their marketing materials. The most influential engineers on the team didn't give a damn about deadlines and thought that being friends with the director would save them, had elaborately set up a plan to blame other engineers they were not friends with, who were on the way to get fired - half the team would never, ever speak to the other half or even be in the same room. I saw a (good) new manager get hired, see the clusterf*ck, and quit because it was hopeless. None of the other managers wanted anything to do with us, we were toxic. Then someone without people management experience got "promoted" to our manager. She told us she didn't care about any of us. Revoked everybody's little privileges, would literally come see if everybody was on their keyboard and typing all the time. Didn't force overtime on anyone but was adamant against people arriving late or leaving early or missing meetings. Started openly taking notes of everybody's failures so she would have ample documentation of who failed what. Told people what to do, didn't want to know the person's opinion about it. A few short months later we shipped.

Best manager I ever had.